Monitoring-circuit for telephone-repeaters



J. F. 100mm. MONITORING CIRCUIT FOR TELEPHONE BEPEATERS.

APPLICATION FILED MAY 18, 1917.

1,361,929, Patented Dec. 14, 1920.

3 SHEETSSHEET I.

INVENTOR ATTORNEY J. F. TOOMEY.

MONITORINC CIRCUIT FOR TELEPHONE REPEATERS.

APPLICATION FILED MAY 18, I9l7.

1,361,929, Patented Dec. 14,1920.

3 SHEETSSHEET 2.

*1 saw-10 m LzneEast Lane "@829 J INVENTOR J17 fbamzy vmmvflm ATTORNEYJ. F. TOOMEY.

MONITORING CIRCUIT FOR TELEPHONE REPEATERS.

APPLICATION FILED MAY 18, 1917.

1,361,929, Patented Dec. 14, 1920.

3 SHEETS-SHEET 3- INVENTOR Tag ATTORNEY UNITED STATES PATENT OFFICE.

MONITORING-CIRCUIT roe Application filed May 18, 1917.

To all whom it may concern:

Be it known that I, JOHN F. TOOMEY, residing at New York, in the countyof New York, and State of New York, have invented certain Improvementsin Monitoring-Circuits for Telephone -Repeaters, of which the followingis a specification.

This invention relates to telephone repeater stations and moreparticularl to the provision of monitoring equipment ior telephonerepeaters whereby the operation of a repeater interconnecting two linesmay be observed.

One of the objects of the invention is the provision of means, wherebyan operator at one type of monitoring station such as, for instance, anobservation station remote from the repeater apparatus, may observe bymeans of a suitable listening set the operation of a repeater duringtelephonic transmission from one line to another through the repeater. I

Another object of the invention is the provision of means whereby anoperator at another type of monitoring station prefer-- ably locatednear the repeater apparatus, so that access may be had thereto forpurposes of adjustment, etc, may connect a monitoring equipment to therepeater and by means of a listening set observe the operation of therepeater during transmission in either or both directions over linesinterconnected through the repeater. Means are also pro vided wherebythe operator at a monitoring station of the second type may disconnectthe repeater from the transmission circuit and directly connect thelines so as to permit of observation of the transmission over the lineswith the repeater disconnected.

Another object of the invention is the provision or" means whereby anoperator at a monitoring station of the second type may eliminate therepeater from an established connection and directly connect the lines,at the same time bridging the operators set d rectly across theinterconnected lines. Means are also provided whereby the operator may,

with the circuit in this condition, apply ring-' 1110' or signalingcurrent over the lines to operate suitable signaling apparatusassociated with the lines.

A further object of the invention relates to the provision of meanswhereby a busy signal will be given if an operator at a monitoringstation of the-first type attempts to Specification of Letters Patent.

AIflER-ICAN TELEPHONE AND OF NEJV YORK.

TELEPHONE-REPEATER-S.

Patented Dec. 14, 1920. Serial No. 169,523.

connect to a repeater with which connection has already been made at astation of the second type. Means are also provided to give a busysignal if an operator at a monitorlng station of the first type attemptsto listen 111 on the repeater circuit when the repeater is disconnected.

Other and further objects of the invention will be clear from thefollowing description taken in connection with the accompanying drawingin which:

Figure 1 is a diagram of the circuit connec tions of the operatorsmonitoring equipment; Flgs. 2 and 3 when placed end to end constitute adiagram 01? the repeater circuits and parts of the monitoring equipmentassociated therewith; and Fig. 1 is a simplified diagram of themonitoring circuit.

The repeater equipment shown in Fi s. 2 and 3 comprises two pairs ofline conductors designated on the drawing as Line East and Line est,said lines terminating in input circuits 1 and 1 of repeaters 2 and 2.The repeaters for convenience of illustration are shown as mechanicalrepeaters but may be of any other type, such as, for instance, the wellknown vacuum tube type. The lines are balanced by correspondingartificial lines L and L The output circuits 3 and 3' or" the repeaters2 and 2 are connected to primaries 1 and 4' of induction coils havingsecondary windings 5, 6 and 5, 6 in the line circuits, and secondarywindings 7, 8 and 7, 8 in the artificial line circuits, the coils beingso arranged that balancing potentials are applied to the input terminalsof the repeaterswith respect to variations received from the outputcircuits 3 and 3'. Relays 9, 10 and 10 are provided, relay 9 operatingwhen energized to open the input circuits 1 and 1 and shortcircuit therepeaters 2 and 2', while relays 10 and 10 operate to disconnect therepeaters from the lines and to interconnect the lines throughconductors 25.

Ass-eciated with the repeater equipment is a monitoring equipment shownin Figs. 1

and 2. There two t ves of monitorin g stations at which the repeater isrepresented by twin jacks J and J The jack J may be mr tiplied at itscorresponding stat-ion if r. red. Jack J may be located at a testboardremote from the repeater apparatus, while ack J, is at positionconvenient to the repeater for purposes of adjustment etc. Operators atthese stations are enabled to listen in on the repeater circuits bymeans of induction coils having primaries 11 and the artificial linecircuits. and 17 connecting primaries 11 and 1 1, to

11f connected-to terminals of jacks J and J said primaries "oein-ginductively related to secondaries 12, '13 and 12, '13 in the linecircuits, and secondaries'l, and 14;, 15 in Conductors 16 i r the tipsprings of jack J may -be disconnected from said windings and connectedto conductors by a relay 18. Should .an op- ,erator attempt to connectwith the repeater by means of jack J when another operator has alreaeyconnected with the repeater at jack J a busy tone will be given thefirst operator overthe contacts of relay 19.

The operators monitoring equipment for use with jack J consists ofreceiver 90 connectedv to the tip contacts of a twin plug P.

:The operators monitoring equipment for use "with ack J is illustratedin F 1g. 1 and comprises .a twin plug P adapted to be inserted in jack Jthe terminals of said plug being connected to transmitter 20 andreceiver21 of an operators set through contacts of keys 22, 23-and 2%.If the plug P is inserted in jack J, receiver 90 will he connected inpar allel with the primaries 11 and 11' overthe tip contacts o f-theplug in such manner that the operator may listen in on the repeater.rircuit without afi'ecting the repeater. If

the plug P is inserted in jack J, the operajtor"s listening set isassociated with" prir ma'ries key 28 to the right, primary 11 isshortcira1 and 11 in parallel. Byth-row-ing cuited and the operator maylisten on Line East? excluslvely. Incoming impulses on "Line Eastare'transmitted to. receiver 21 without amplification but outgoingimpulses are transmitted after being amplified by repeater 2. Similarlyby throwing key 28 to the left the operator can listen on Line lVestexclusively. f The operator is thus enabled to determine whether theamplificaticn-in each direction is satisfactory. By throwing key. 22 totheleft, or cut-out .position relays 9, lOl-and 10 may beenergized todisconnectthe lines from .tlie repeater and 11,111 the. operator canthus listen in on the transmission thus under this condition "witlthetransm ssion when the repeater is 55,

interconnect them over circuit 25. As the operators receiver isconnected to-primaries the 'ljineswitheut the repeater and compare incircuit. By throwing key 22 to the right or; =ta'ik1ng positiontheopera'tors transmitts-r, which is not normally connected tothe-circuitis-connected to conductors 16, 17 and the relays 9,10 and 10?are operated to disconnect the repeaterand interconnect the lines overconductors 25. At the same time conductors 16 and 17 are disconnectedfrom the pr1-mar1es11 and 11 and bridged across conductors-25 by meansof the contacts of therelay 18 ;,so that the .ope rators set is follows:and plu of plug ,bridged directly across the connected lines.

Withswitch 22 in this position ringing key I 2% may be throwntoapplyieither 16 cycle or v133 cycle ringing current over the'linesconnected through the conductors 25 to operate si naling apparatusassociated with the lines at a distant station. With this generaldescription in mind the invention may now be fully understood from adescriptionof the operation. i

For convenience the sheets of the drawing including Figs. 1, 2 and 3should be arranged end to end with Fig 1 on the left and F-ig. 3 ontheright. Assuming that an operator at the monitoring station at which therepeater is represented loyqack J desires to observe the operation ofthe repeater, the plug P will be inserted in jack J 7 completing acircuit from battery over the sleeve contacts of plug P and jack Jthrough the winding of relay 26 to ground. 7 Normally windings 11 and 11are shortcircuited, the circuit of winding 11 extending from the lefthand terminal of said winding to point 27, thence over conductor 28,lower contact of relay 2 6,..contactn'29' {of jack J conductor 16,con-tact 30 of relay 18 to right. hand terminal of winding 11. Similarlythe circuit of winding 11{ extends 'fromtheleft hand terminal thereoitopoint 27,10Ver con-' duct-or 28, lower contact'of relay 26, contact Frompoint127 over conductor 28, contact 13'01 relay 19,upper tip contacts ofjack J g receiver 90, lower tip contacts -8 and jack J, contact 53 ofrelay 19, to terminal 54: where the circuit divides,one path continuingover contact 29 ofjack J conductor 16, contact of relay18, and

through winding 11 baclr to point 27, and the other path extending inparallel thereto from terminal 5 L over contact 8110f jack J conductor17-, contact32of relay"18," and through WlIlCllllgll' back to point 27.,r 1

The operator may nowlisten in outhe lines interconnected through" therepeater without affecting therepeater. .;Inc o ming voice cur-rentsfrom Line East actuate reput circuit 8 act through winding 4; to in ducepotential variations in windings 5f, 6, 7 and 8 whereby said amplifiedvoice currents from Line East are transmitted over Line lVesti andartificial line L., "llhe' .peater- 2 and the amplified currents inoutpotentials inv Line West and line L""-are 113a battery.

in such direction that the input terminals of repeater 2 are at pointsor" equal potential so that no effect is produced on repeater 2. At thesame time these potentials act cumulatively as to coils 12, 13, 14 and15 to induce potential variations in winding 11, whereby the amplifiedvoice currents are transmitted to receiver 90 over the circuit alreadytraced. Similarly voice currents coming in over Line est are amplifiedby repeater 2 and thus amplified, are transmitted over Line East therebyactuating reoeiver 90 through inductive action on winding 11.

The operator at the monitoring station at which jack J is located maydisconnect the repeater from the lines and interconnect the linesthrough conductors by withdrawing plug P and inserting an idle plug inthe lower'half of twin jack J, thereby closing a circuit from ground,contacts 56 and 57 of jack J, contact 58 of relay 59, and throughwinding of relay 60 to battery. Relay 60 upon being energized closes thefollowing circuits: 4

From ground, lower contact of relay 60, winding of relaylO, and windingof relay 9 to battery, and from ground, upper contact of relay 60,winding of relay 61, wind-- ing of relay 10 and winding of relay 9 toRelays 9, 10, 10 and 61 are energized. Relay 9 operates to open theinput circuits 1 and 1 and shortcircuit repeater elements 2 and 2.Relays 10 and 10 disconnect the lines from the input circuits of therepeater elements and interconnect the lines through conductors 25Should another operator at the same type of monitoring station insert aplug into a multiple of jack J in an attempt to bridge an open ators setacross the tip contacts of such jack, relay 26 would be energizedthereby closing a circuit from ground, over upper contact of relay 26,contact of relay 61 (now energized), through winding of relay 19 tobattery. Relay 19 operates t open contacts and 53 and close contacts 63and 64:, thereby applying a busy tone to the tip springs of jack J andits multiples, so that he operator receives a busy signal indicatingthat the repeater is either disconnected or under the control of anothermonitoring operator. 7

Assuming nowthat an operator at the V monitoring station at which therepeater is represented by jack J, desires to connect with the repeater,the twin plug P of an operators monitoring equipment such as illustratedin Fig. 1 is inserted in the twin jack J thereby closing an energizingcircuit for relay 59 from battery, sleeve contacts of plug P, and jack Jwinding of relay 59 to ground. Relay 59 pulls up, opening its contact 58and closing contacts 65 and 66. The closing of these contacts does notat this time produce any effect. Upon inserting the plug P in jack J however, the operators receiver 21 is bridged across the windings 11 and 11as shown in the simplified diagram of Fig. 4. The circuit may be tracedas follows:

From point 27, over conductor 28, contact 6? of jack J over contacts 68and 69 of key 23 in parallel, over conductor 70, contact throughreceiver 21, contact 86, conductor T1 to spring 72 where the circuitbranches, one path continuing over contact Y3, contact 7 1, conductor13, upper tip contacts of plug 1, and jack J conductor 16, contact 30,and through winding 11 back to point 27', the other path continuing fromspring 72 over contact 75, contact/(6, conductor 52, lower tip contactsof plug P and jack J conductor 17, contact 32 of relay and throughwinding 11 to point 27. If the operator desires to listen in on LineEast exclusively, key 23 may be thrown to the right or E positionthereby shortcircuiting winding 11 as indicated schematically in Fig. 4with switch S in dotted line position. The receiver 21 is now in circuitwith winding 11 over the circuit already traced, while the shortcircuitfor winding 11 may be traced as follows:

From point 27, over conductor 28, contact 67, contacts 77 and T8 of key23, contact 76 of key 22, conductor 52, lower tip contacts or plug P andjack J conductor 1'2" contact 32, and through winding 11 to point 27.

in a similar manner by throwing key 23 to the left r 1V position,winding 11 may be shortcircuited through contacts 79 and 80 of he 23,the winding 11 remaining in circuit with the receiver 21, so that the operator may listen in on Line est exclusively. The result is indicated ina con ventional manner in Fig, 4 with the switch S1 in dotted lineposition.

tihould the operator desire to disconnect the repeater, key 22 may bethrown to the leior out out position, thereby closing a key, contact 66of relay 59, (now op rated), winding of relay 60 to battery. Relay 6Opulls up and closes circuits already traced through relays 9, 10, 10 and61 whereby the repeater is disconnected and the lines interconnectedthrough conductors 25 in a manner already described. As the receiver isconnected with windings 11 and 11. over the circuits above traced, thetransmission over the lines with the repeater disconnected be observedand compared with the transmission with the repeater in circuit.

Should the operator desire to talk over the lines, key 22 may be thrownto the right talking position, closing a circuit over i contact 33 forrelay 84, whereby the receiver 21 is connected in parallel with windingThe operation of key 22 also closes a circuit from ground over contact82 to terminal 83 where it branches, one path extending over contact 84,contact 66, winding of relay 60 to battery, and the other pathcontinuing from terminal 83, over contact 65 of relay 59, (nowoperated), through winding of relay 18 to battery. Relays 60 and 18 areenergized,

the former; actuating means to disconnect the repeater and interconnectthe lines di- 'rectly through conductors 25 in a manner alreadydescribed, and the latter operating to open contacts 30 and 82 and closecontacts 85' and 86, whereby conductors 16 and 17 are disconnected fromwindings 11 and 11 andconnected to conductors 25. The operators ,set isnow bridged directly across the common terminals or the interconnectedlines, the bridge being traced as follows:

From point87, over contact 85, conductor 16, upper tip contacts of plugP and jack J 'conductor 43, contacts 44, and 46, conductor 47, winding41, winding 39 and receiver'21 in parallel, conductor 48, contacts 49,and 51, conductor 52, lower tip contacts of plug P and pack J conductor17, contact 86'to point 88. The operators set is connected directly tothe line and the repeater disconnected for the reason that if i the setwere connected to'theline a condition of unbalance would occur whichwould' set up singing. By directly connecting the set to the linestransformer losses are avoided.

By manipulation of the ringing key 24,

i the o erators set 'ma be disconnected from O ioyrcle current beingapplied if the key is' thrown to the right. enabled to test signalingapparatus assothe bridge above traced and ringing current appliedthereto, 16 cycle'current being ap plied if the key is thrown to theleft, and 183 The operator is thus ciated with the lines and responsiveto ringing current.

If at anytime while an operators set is connected to the line throughjack J another operator plugs into jack J the latter operationresults'in the energization of re-v lay 26 in a manner alreadydescribed, whereby a circuit is closed. from ground over upper contactof relay 26, contact 89 ofijack J (closed by the insertion of plug P andthrough -wind1ng of relay 19 .to battery,' energizing said relay,whereby contacts 43" and 53 are opened and contacts 63 and 64 I areclosed to apply a busy tone to the operators set connected to the tipcontacts of jackJ. i

VVh'ile the invention has been illustrated ganization itis to beunderstood that it is capable of embodiment in many and widely variedforms without departing from the scope ofthe appended claims.

and described as embodied in a specific or- 7 What is claimed is 1. Incombination with a telephone re-' peater, monitoring stations at whichthe operation of said repeater may be observed,

monitoring equipment at said stations, and means whereby when monitoringequipment is associated with said repeater at one of saidstations, abusy test will be applied to .monitoringequipment at the other station.

2. In combination, transmission lines, a

repeater interconnecting said lines, a moni toring station, terminals oisaid repeater at said station, means whereby the repeater may bedisconnected from the lines, and means whereby when the repeater isdisconnected from the lines a busy test is applied to said terminals. Vor 3. In combination, transmission lines, a repeater interconnectingsaid lines, a monitoring station, multiple terminals of said repeater atsaid station, means'cooperating with one of said terminals whereby there- 5. In combination with. a repeaten'a plurality of monitoringistations, .monitoring equipment at sa d stations, terminalscorresponding to the {repeater at each of said stations wherebymonitoring equipment may 7 be associateclwvitli said repeater, and meanswhereby when monitoring equipment is associated with said repeater overthe terminals of one of said stations a busy signal will be applied to amonitoring equipment applied to the repeater terminals at the otherstation. a

in opposite directions,transmission lines interconnected through therepeater, monitoring station, monitoring equipment at said station, andmeans whereby said monir r ,110 6. In combination with a rrepeater'comflprising two-repeater elements for repeating toring equipment maybeassociated 'witli'the V circuit of each ofisaid'repeater elementsindependently of said lines e In comb nat on with a repeater comprisingtwo-repeater elements for. repeating in opposite directions,transmissionlines in- -terconnected through therepeater, an pera tors set, and meanswhereby said set may be connected with the circuit of each of saidrepeater elements independently" of .said

transmission lines.

r 8. In combination'witha repeater having a, plurality of outputcircuits, an operatoids" circuit, induction coils .for associating theoperators circuit with each of said output circuits, and an operatorsset in a bridge with said induction coils in parallel with respectthereto.

, 9. In combination with a repeater having a plurality of outputcircuits, an operators circuit, induction coils for associating theoperators circuit with each of said output circuits, a bridge connectionshortcircuiting said induction coi s, an operators set, and meanswhereby said set may be connected in said bridge.

10. In combination with a repeater having a plurality of outputcircuits, an operators circuit, induction coils for associating theoperators circuit with each of said output circuits, an operators set ina bridge with said induction coils in parallel with respect thereto, andmeans for shortcircuiting said induction coils at will.

11. In combination with a repeater having a plurality of outputcircuits, an operators set, means for associating said set with all ofsaid output circuits, and means operable at will for disconnecting saidoperators set from certain of said output circuits whereby the set mayremain associated exclusively with the other circuits.

12. In combination, transmission lines, a repeater for interconnectingsaid lines, monitoring equipment, means for associating said equipmentwith the repeater, and means .operable only when the equipment is soassociated for disconnecting the repeater from the transmission lines.

13. In combination, transmission lines, a repeater for interconnectingsaid lines, an independent circuit for interconnecting said lines, amonitoring equipment including an operators set, means for associatingsaid equipment with the repeater, and means operative at will fordisconnecting said repeater and connecting said lines through saidindependent circuit, and for associating said operators set with saidindependent circuit.

14. In combination, transmission lines, a

repeater for interconnecting said lines, an

operators set with said independent circuit, and means for applyingringing current to said independent circuit.

15. In combination, transmission lines, a repeater for interconnectingsaid lines, an operators equipment including a transmitter and areceiver, means for associating said equipment with a plurality of saidlines with the receiver in separate inductive relation to each line, sothat voice currents transmitted over the lines and through the repeaterwill actuate said receiver, and means operative at will for directlyconnecting said receiver with said lines independently of the repeater.

16. In combination, transmission lines, a repeater for interconnectingsaid lines, an operators equipment including a transmitter and areceiver, means for associating said equipment with a plurality of saidlines with the receiver in separate inductive relation to each line, sothat voice currents transmitted over said lines and through saidrepeater will actuate said receiver, and means operative at will fordirectly connecting said re ceiver with said lines independently of therepeater and for associating said transmitter therewith.

In testimony whereof, I have signed my name to this specification thiseleventh day of May, 1917.

JOHN F. TOOMEY.

